Air conditioning system



g- 1 L. A. PHILIPP 2,159,900

AIR CONDITIONING SYSTEM Original Filed March 7, 1934 INVENTOR. 4 9mg P1412 2 w BY -Patent e'd Aug.15,1939

mesne assignments, to Nash-Kelvinator Corporation, Detroit, Mich., acorporation of Maryland Application March 7, 1934, Serial No. 714,432

, Renewed January 11, 1939 10 Claims.

The present invention relates to air conditioning systems andparticulai'ly to systems for cooling and dehumidifyingair, and is basedupon the subject matter disclosed and claimed in my copendingapplications, Serial Nos. 697,169, 697,170, 697 ,171 and 697,172 filedrespectively on November 8, 1933.

One of the objects of the present invention, is to provide a heatabsorber over or about which 10 air is circulated which heat absorber,at times,

is maintained at such low temperature as to cool the air to considerablybelow the dew point thereof for the purpose of removing moisture fromthe air, to provide another heat absorber which, whenever it is inoperation, operates constantly independently of the first heat absorberand which is utilized for removing principally sensible heat from airflowing over or about the same, and to provide for controlling theamount of heat removed by the heat absorbers in accordance with thecondition of the air; in carrying out the foregoing object, it is afurther object to control the system in accordance withthe'relativehumidity and the temperature of the air.

25 Further objects and advantages will be apparent from the followingdescription, reference being had to the accompanying drawing wherein apreferred form of embodiment of the present invention is clearly shown.

30 The figure in the drawing represents diagrammatically an airconditioning system.

The air conditioning system is herein shown, for illustrative purposes,for cooling a room such as a living room or an office and the room 20,and

35 the roqm is diagrammatically illustrated by a side wall 2|.and afloor 22. Within this room there is disposed a cabinet 23 havingcompartments 24 and 25. A partition 26 depends from the top wall 31 ofthe cabinet and extends from 40 the front to the rear thereof to dividesaid cabinet a 23 into the compartments 24 and 25. Air enters thecompartment 24 and is expelled from compartment 25 through openings 29and 30 respectively in the top-2l. Air is forced through the 45 cabinetby the fan 3| which is driven by a constantly operating motor 32. 1

A heat absorber 34, having fins 36 thereon for increasing the heatabsorbing area thereof, is disposed within compartment 24 and is hereinshown, for the purpose of illustrating one form of the invention, as anevaporator. Gaseous refrigerant is withdrawn from the evaporator 34through a pipe 35 by the cylinder 31 of a compressor 38. The compressedrefrigerant is deliv- 56. ered to a condenser 33 wherein it is cooledand known in the art as a thermostatically controlled expansion valveand such valve is shown in the Marshall Patent No. 630,617 and isemployed as shown in the Marshall Patent No. 1,003,283. For the purposeof subjecting the expansion valve to the temperature at the outlet ofthe evaporator, a bulb 46 is intimately connected to the suction pipe 35and is connected by a pipe 48 to theback side of the flexible wall ofthe valve 44. The bulb 46 and the pipe 48 contain a volatile fluid toaffect the operation of the valve 44 so that it will operate also inaccordance with changes in temperature of the outlet of the evaporator.

The operation of the compressor 38 will cause a loweringof the pressureand likewise a loweringof the temperature of the evaporator 34 and airflowing over evaporator 34 will be cooled. The size of the compressor iscomputed relative to the size of the evaporator so that during normaloperation, only or principally sensible heat will be removed from theair as it flows over evaporator 34.

A second heat absorber 50 is also disposed within compartment 24 and isshown as an evaporator having fins 5| for increasing the heat absorbingsurface thereof. Gaseous; refrigerant is withdrawn from evaporator 50 bya pipe 52 which pipe is connected through a valve 53, coupling 55 andpipe 51 to the low pressure side of a cylinder 58 of compressor 38. Thecondensed 40 refrigerant is cooled by the condenser 39 and the liquidrefrigerant is conducted from the receiver 40 through the pipe 4|coupling 42 and a branch pipe 60 to an expansion valve 6|. Thisexpansion valve may be of the same type as 45 valve 44 and is responsiveto the pressure within the evaporator and the temperature at the outletof the evaporator, it also being provided ,with a bulb 46 and aconnecting pipe 43. The

capacity of the cylinder 58 is computed relative 50 to the size ofevaporator 50 so that when the valve 53 is open, the pressure withintheevaporator 50 is decreased to such an extent that the evaporator willcool the air flowing thereover to considerably below the dew pointthereof,

ing the precipitation of moisture from the air to reduce the relativehumidity thereof. The water will drip from the evaporator to the bottomof the cabinet 23 and will be drained therefrom through the drain pipe63.

A restriction bypasses the valve 53 and is herein shown as a restrictingpipe 64 which is connected between pipe 52 and coupling 55. When thevalve 53 is closed, the restriction 64 permits a restricted flow ofgaseous refrigerant from the evaporator 58 to the compressor 38 and thearrangement is such that when valve 53 is closed, the quantity ofgaseous refrigerant withdrawn from evaporator 50 is sufficient only tocause the evaporator 50 to be lowered in temperature to remove only orprincipally sensible heat from the air.

The desired temperature of the air is maintained by causing thecompressor 38 to operate intermittently. The compressor is driven by amotor 85 and the starting and stopping of the motor is controlled by athermostat T. This thermostat may be placed at any desired place in theroom and when the temperature of the air is above a predetermineddesired maximum, it closes the motor circuit including wire 66,thermostat T, wire 61, motor 65 and wire 68. The refrigerating apparatuswill then operate to reduce the temperature of the air flowing over theevaporators 34 and 5| and when the temperature of the air is decreasedto a predetermined relatively lower temperature, the thermostat T willinterrupt the motor circuit. 1

It is also desirable to control the relative humidity of the air and forthis purpose there is provided a humidostat H for controlling the valve53. The valve 53 is magnetically operated and includes a solenoid core10 which functions as a valve and is lifted from its seat when themagnet coil II is energized. The valve II is energized when the relativehumidity of the air in the room is high and this valve is maintainedopen until the relative humidity is decreased to a desired minimum atwhich time humidostat H will interrupt the circuit to the coil 'II andwill maintain same interrupted until the relative humidity increases toa certain higher value. circuit for the coil includes wire 66,thermostat T, wire 12, humidostat H, wire 13, coil H and wires 14 and88. When the relative humidity of the air is higher than that desired,the flow of gaseous refrigerant fromthe evaporator 50 is unrestrictedand therefore the temperature of the evaporator will be decreased tobelow the dew point of the air causing a precipitation of moisture and aconsequent dehumidification 'of the same. After the relative humidity ofthe air.

has been decreased to a desired lower value, the valve 53 will close andthe flow of gaseous refrigerant from evaporator 50 will be restricted tothat which can flow through the restricting pipe 64. The evaporator 50will thenincrease in temperature and only or principally sensible heatwill be removed from the air.

The air after passing over evaporators 34 and 50 will thoroughly mix inthe bottom of the cabinet 23 and in the compartment 251 Therefore therelatively cold air from evaporator 50 will be tempered by therelatively warm air from evaporator 34.

It is desirable to cause a continuouscirculation of air in the room 20and therefore the fan motor 32 operates continuously, it being connectedas follows, wires 66 and 18, motor 32 and wires 11, 14, and 88.

The

Although I have shown the heat absorber 34 as comprising an evaporatorof a mechanical refrigerator, it is to be understood that any suitabletype of heat absorber may be employed. When the heat absorber 34 is inthe form of an evaporator and as herein shown operatively connected withthe compressor 38, it is desirable that the low pressure side of therefrigerating system be maintained independent of one another so thatwhen the compressor cylinder 58 is operating to produce a relatively lowpressure, gaseous refrigerant from evaporator 34 will not flow to thelow pressure side of the refrigerator system including evaporator 58 andcylinder 58. Gaseous refrigerant from pipe 51 is connected to the crankcase 18 of compressor 38 as is well known in the art while the pipe 35does not enter the crank case and therefore the low pressure sides ofboth systems are maintained entirely independent of one another. The oilwhich is usually contained in the crank case 18 for lubricating theworking parts of the compressor 38 is usually miscible with therefrigerant employed and consequently some of the oil flows through thecondenser 38, receiver 40 and into the evaporators 34 and 50. The oilfrom evaporator 50 can return directly to the crank case 18 because thepipe 51 is connected with the crank case. In order to return oil fromevaporator 34 to the crank case .without subjecting the crank to therelatively higher pressure in pipe 35, the pipe 35 extends through afloat chamber which incloses a float 8 l,which float actuatesaneedlevalve 82. The bottom of the chamber 80 is connected with a pipe 83, theinlet of which is controlled by the valve 82. After a predeterminedquantity of oil is returned to the chamber 80, the float 8| will rise tolift the needle valve 82 and permit the oil to flow into pipe 83 and bereturned to the compressor crank case 18 by said pipe.

Under certain conditions it will be desirable to cause someprecipitation of moisiture at the absorbers 34 and 50 when theseabsorbers are operating at substantially the same temperature, and it isto be. understood that when the absorber 34 is referred to asfunctioning to remove only or principally sensible heat, such term is'used merely to define the main functional purpose of said absorber 34as distinguished from the main functional purpose of absorber 50 whenabsorber 58 is operating at a relatively lower temperature than absorber34.

While the form of embodiment of the present invention as hereindescribed constitutes a preferred form, it is to be understood thatother forms might be adopted, all coming within the scope of the claimswhich follow.

I claim:

1. An air conditioning system comprising in combination, a heat absorberabout which air to be conditioned is circulated; a second heat absorberoperating constantly independently of the first heat absorber and aboutwhich air to be conditioned is circulated, two independent refrigerantwithdrawing means formaintaining said constant independent operationbetween said two heat absorbers, and means responsive to the relativehumidity of air for varying the cooling effect of one of said heatabsorbers relative to the other.

2. An air conditioning system comprising in combination, a heat absorberabout which air to be conditioned is circulated; a second heat absorberoperating constantly independently of the first heat absorber and aboutwhich air temperature of the air for controlling the amount of heatabsorbed .by the specific heat absorbers; and means responsive to therelative humidity of such air for varying the cooling effect of one ofsaid heat absorbers relative to the other.

3. An air conditioning system comprising in combination, a heat absorberabout which air to be conditioned is circulated; a second heat absorberoperating constantly independently of the first heat absorber and aboutwhich air to be conditioned is circulated, two independentrefrigerant-withdrawing means for maintaining said constant independentoperation between said two heat absorbers, means responsive to thetemperature of the air for controlling the amount of refrigeratingmediums flowing through said heat absorbers; means responsive to therelative humidity of. the air for varying the amount of refrigerantflowing through one of said heat absorbers relative to the other.

4. An air conditioning system. comprising in combination, a plurality ofevaporators about which air to be conditioned is circulated, sepa rateand independent sources of low pressure withdrawing means, meansconnecting said sources to the respective evaporators for constantindependent operation of the evaporators, and means responsive to thetemperature and humidity conditions of the air for controlling theamount of heat absorbed by the evaporators.

5. An air conditioning system comprising in combination, a plurality ofevaporators about which air to be conditioned is circulated, separateand independent sources of low pressure withdrawing means, meansconnecting said sources to the respective evaporators for constantindependent operation of the evaporators, and means responsive to therelative humidity of the air for controlling the operation of one ofsaid evaporators.

6. An air conditioning system comprising in combination, a plurality ofevaporators about which air to be conditioned is circulated, separateand independent .sources of loiii pressure withdrawing means, meansconnecting said sources to the respective evaporators for constantindependent operation of the evaporators. a.

, the other.

valve for controlling the flow of refrigerating medium through one ofsaid evaporators, and means responsive to the relative humidity of theair for controlling said valve.

7. An air conditioning system comprising in combination, a pair of heatabsorbers operating constantly independently of one another, and aboutwhich air to be conditioned is circulated, two independent refrigerantwithdrawing means for maintaining said constant independent operationbetween said two heat absorbers, and means responsive to a change in therelative humidity of the air for changing the temperature of one of saidabsorbers relative to one another.

8. An air conditioning system comprising in combination, a pair of heatabsorbers operating constantly independently of one another, and aboutwhich air to be conditioned is circulated, two independent refrigerantwithdrawing means for maintaining said constant independent operationbetween said two heat absorbers, and means responsive to the temperatureof the air for controlling the heat exchange between the air and theheat absorbers, and means responsive to a change in the relativehumidity of the air for changing the temperature of one of saidabsorbers. relative to one another.

9. An air conditioning system comprising in combination, a pair of heatabsorbers for cooling air, heat dissipating means having two inlets,said heat absorbers being connected with the heat dissipator, one toeach inlet, so that the temperatures of the heat absorbers aremaintained constantly independent. of one another, and means responsiveto the relative humidity of the air for varying the cooling effect ofone of the heat'absorbers relative to the other.

10. An air conditioning system comprising in combination, a pair of heatabsorbers for cooling air, heat. dissipating means having two inlets,said heat absorbers being connected with the heat dissipator, one toeach inlet, so that the temperatures of the heat absorbers aremaintained constantly independent of one another, means responsive tothe temperature of the air for controlling the amount of heat absorbedby the absorbers, and means responsive to the relative humidity of theair for varying the cooling efiects of one of the heat absorbersrelative to LAWRENCE A. PHILIPP.

